Fbmaj13 chord

The F-flat major thirteenth chord (abbreviated Fbmaj13 chord) is a seven-note chord consisting of the notes F♭, A♭, C♭, E♭, G♭, B♭♭, and D♭. The chord is formed by adding a thirteenth to the F-flat major eleventh chord.

In practice, the fifth (C♭) and eleventh (B♭♭) are often omitted from the Fbmaj13 chord to avoid a very dissonant sound, and because it's not always possible to play all notes simultaneously.